Cementitious Materials Science

Theories and Applications

Lin Zongshou, Xing Weihong, Chen Wei, Lin Zongshou

• Publisher: De Gruyter
• Year: 2019
• ISBN:
  9783110572162
• Edition: 1
• Topic: Technology & Engineering
• Subtopic: Materials Science
• Index: Technology & Engineering

With a focus on portland cement, the book systematically illustrates the composition, properties, and applications of different kinds of cementitious materials, and presents their reaction during the hydration and hardening process. The production technique and applied technology are also discussed with examples. Exercises are added in each chapter, making the work an essential textbook for students.

1 Introduction

1.1 Definition and classification of cementitious materials

On the basis of the physical and chemical effects, in the process of the gradual transformation of plastic slurry into a solid stone, the substances that can bind other materials to form a whole structure with mechanical strengths are collectively referred as cementitious materials, also known as glued materials.

Cementitious materials can be generally divided into two categories: inorganic and organic types. All kinds of resin and asphalt are organic cementitious materials. The inorganic cementitious material can be divided into hydraulic and nonhydraulic types based on its hardening conditions. The hydraulic cementitious material, after mixing with water, can be hardened both in air and in water and generate strength, which is normally called cement, such as Portland cement, aluminate cement, sulphoaluminate cement and so on. Instead of hardening in water, the nonhydraulic cementitious materials could be hardened in air or other conditions. The one that can only be hardened in the air are called air-hardening cementitious materials, such as lime, gypsum and magnesium cementitious materials.

On the basis of the classification of hydration products, the inorganic cementitious materials can be divided into silicates that mostly produce calcium silicate hydrate, aluminate that mostly produce calcium aluminate hydrate, sulphoaluminate that mostly produce calcium sulphoaluminate hydrate and so on. In addition, there are also some other classification methods.

1.2 The role of cementitious materials in national economy

Cementitious materials can not only be widely used in industrial constructions, civil engineering, transportation, water conservancy, agriculture and forestry, national defense, seaport, urban and rural constructions, aerospace industry, nuclear industry and other new industrial constructions, but also replace steel and timber to produce sleeper, electrical pole, pressure pipe, cement carrier and various structures used for marine development and so on. Besides, it is also an indispensable material for a series of large-scale modern technical facilities and national defense engineering. Therefore, as one of the most important raw materials, cementitious materials have attracted a significant attention.

In the foreseeable decades, cement, concrete and other cementitious materials are still the main building materials. With the development of science and technology, the ability of mankind to transform nature has been continuously improved, and the scale has gradually expanded, which simultaneously has put forward a series of new requirements for the cementing materials. Therefore, the cementitious material has a broad development prospects. The reasons for the continuous development of cementitious materials should be attributed to the following characteristics:

• (1) abundant raw materials, raw materials locally available, low production costs;
• (2) good durability, high adaptability, can be used in water, sea, hot or cold environments;
• (3) advanced fire-resistance capacity;
• (4) less maintenance work, low depreciation costs;
• (5) as a substrate, it is capable to combine or composite with other materials, such as fiber-reinforced cementitious materials, polymer-reinforced cementitious materials, fiber–polymer–cementitious material multiple composites and so on. Based on the aforementioned points, a large category of new composite materials could be developed;
• (6) beneficial for reusing industrial wastes.

The applications of cementitious materials have played an important role in all aspects of industry and civil engineering, and the cementitious material industry is an industry that cannot be ignored in the national economy. With the development of modern science and technology, new technologies in other fields will also inevitably penetrate into the cementitious material industry. The traditional cementitious material industry is bound to spring up the new technology revolution and varietal development with the rapid growth of science and technology. Simultaneously, its application areas will also be broadened, which could further strengthen its key role in the national economy.

1.3 The brief history of cementitious materials

The development of cementitious materials can be traced back to the prehistoric period of mankind. It has gone through several stages such as natural clay, gypsum-lime, lime-volcanic ash and hydraulic cementitious materials made from artificial ingredients. The ancient Egyptians used the Nile’s slurry to make bricks without calcination. To increase strength and reduce shrinkage, sand and grass are also mixed into the mud. About 3,000–2,000 BC, the ancient Egyptians began to use calcined gypsum as a building cementitious material, and calcined gypsum has already been used in the construction of the ancient pyramids in Egypt.

Unlike the ancient Egyptians, the Greeks preferred to use the lime generated from calcined limestone in the construction of buildings. In 146 BC, the ancient Roman Empire conquered the ancient Greece, inheriting the tradition of producing and using lime in ancient Greece. The ancient Romans used lime by first dissolving it with water, mixing it with sand and then building the structures with the mortar. Some of the ancient Roman architecture, which was built with lime mortar, was very strong and remains even until today.

The ancient Romans improved the utilization technology of lime. Not only the sand was mixed in the lime, but also the ground volcanic ash. In the areas without volcanic ash, it was replaced by the ground brick, which had the same effect as that of volcanic ash. The mortar was much better in strength and water resistance than the lime–sand two-component mortar, and it was more durable in its regular buildings and underwater construction. Some people called the “lime–ash–sand” three-component mortar “Roman mortar.”

The development of Chinese construction cementitious materials is unique and historical. As early as 5,000–3,000 BC, the period of Yangshao culture in the Neolithic, Chinese have already used “white ash” to daub the cave, the ground and the four walls of the excavation, which can result in a smooth and hard structure. The “white ash” was named because of its white powder appearance, which was made from grinding natural ginger stone. The ginger stone is a kind of limestone with high silica content. It is often mixed in the loess, and it is the calcareous concretion in loess. The “white ash” is the earliest building cementitious material that has ever found in ancient China.

In the sixteenth century BC, Shang Dynasty, the cave buildings were rapidly replaced by wooden structure. At this time, in addition to using “white ash” to daub the ground, the yellow mud was used to build walls. From 403 BC to 221 BC, the Warring Stage period, the grass was mixed with yellow mud to build walls and glue wall tiles. In the history of Chinese architecture, the “white ash” was eliminated long time ago. However, the yellow mud and yellow mud mixed with grasses as cementitious materials were utilized until modern society.

In the seventh century BC, lime appeared in the Zhou Dynasty, which was mainly made from the calcined shell of the large clam. The main component of clam shell is calcium carbonate. When CO2 is exhaustively eliminated, the remaining substance is lime. It has been found in the Zhou Dynasty that the produced lime has good moisture absorption and resistance properties, which is the reason why it has been widely used in Chinese history for a long period.

In the fifth century, South and North Dynasties, a kind of building material named “three-mixture-soil” appeared, which was composed of lime, clay and fine sand. In the Ming Dynasty, the “three-mixture-soil” was composed of lime, pottery powders and gravels. In the Qing Dynasty, except for the lime, clay and fine sand-based “three-mixture-soil,” the lime, slag and sand were utilized to produce a new “three-mixture-soil.” Based on the modern point of view, “three-mixture-soil” can be treated as a kind of concrete, in which the lime, loess or other volcanic ash materials were utilized as cementitious materials and fine sand, gravel or slag played the role of fillers. There are many similarities between the “three-mixture-soil” and the three-component mortar (Roman mortar). After tamping, the “three-mixture-soil” has relatively high strength and good waterproofness capacity. It was used to build dams in the Qing Dynasty.

One of a striking feature for the development of cementitious materials in Chinese ancient architecture is the application of cementitious materials composed of organic materials and lime, such as “lime-glutinous rice,” “lime-tung oil,” “lime-blood,” “lime-bletilla,” “lime-glutinous rice-alum” and so on. In addition, in the application of “three-mixture-soil,” the glutinous rice and blood were also added.

The development process of the cementitious materials in ancient Chinese architecture originated from “white ash” and yellow mud, which further transferred to the lime and “three-mixture-soil,” and finally developed to the cementitious materials of lime doped with organic materials. The cementitious material in ancient Chinese architecture had its glorious histories. Compared to the development of that in ancient western architecture, due to the widespread adoption of the cementitious material of lime and organic materials, the Chinese ancient cementitious materials were even better.

In the second half of the eighteenth century, hydraulic lime and Roman cement were developed, which were made from calcined limestone containing clay. Based on this foundation, a natural cement was developed from calcined and finely ground natural cement rock (a limestone with clay content at 20–25%). Subsequently, it gradually developed to grind and mix the limestone with a certain amount of clay, and produced the hydraulic lime based on the calcination of artificial ingredients. This is actually the prototype for Portland cement production.

In the early nineteenth century (1810–1835), according to artificial ingredients, high-temperature calcination and grinding, the hydraulic cementitious materials can be produced. The calcination temperature has reached the melting points of several raw materials, which can also be treated as sintering. In 1824, the British Joseph Aspdin first obtained the patent for the product. Since the produced cementitious material has similar appearance and color in the hardened state as that limestone produced on Portland Island, it was originally called Portland cement. In our country, it was called silicate cement. Due to the fact that it has relatively high silicate content, the Portland cement can harden in water and show relatively high strength. An example of the first large-scale application of Portland cement was the Thames Tunnel Construction, which was built in 1825–1843.

The appearance of Portland cement has played an important role in engineering construction. With the demands of modern science and industrial development, in the early twentieth century, various cements for different applications were gradually produced. In the recent half of the century, sulphoaluminate cement, fluoroaluminate cement, aluminoferrite cement and other types of cement were successively developed, which promote further development of Portland cement to more categories. At the same time, new cognition has been acquired on ancient cementitious materials such as lime and gypsum, which enlarge their application fields and development speed. Today, cementitious materials have entered a stage of vigorous development.

1.4 The development of cementitious materials science

In the broad field of productive and scientific practice for cementitious materials, considerable knowledge has been accumulated, especially with the formation and development of materials science, new and profound changes are taking place in the understanding of cementitious materials. The characteristics and trends of this change can be summarized as follows:

• (1) The understanding of cementitious materials is gradually deepened, from macroscopic to microscopic, which gradually reveals the relationship between its performance and the internal structure. Thus, this provides a theoretical basis for developing new varieties of cementitious materials and expanding their areas of applications.
• (2) The understandings for cementitious materials productive process and their hydration and hardening process have gradually improved from experience and phenomenon to theory and essence, which provides a theoretical basis for effectively controlling the productive process of cementitious materials products and adopting new technologies and new methods. There is no doubt that cementitious materials are being formed progressively as an important part of material science.
• (3) The traditional cementitious materials were produced by natural raw materials. In future, no natural resources would be used for the production of cementitious materials, while various industrial solid wastes could be the main raw materials to produce near-zero emission environment-friendly cementitious materials with simple manufacturing process and little energy consumption.

The main research contents of cementitious materials can be summarized as follows:

• (1) the relationship between composition, structure and cementitious properties of cementitious materials;
• (2) the law of hydration and hardening process and structure formation of cementitious materials;
• (3) the relationship between composition and structure of harden cementitious materials and their engineering properties;
• (4) preparation of cementitious materials with specified properties and structure and technological approaches for the production of environment-friendly cementitious materials.

We are convinced that with the development of cementitious materials science, the cementitious materials and products industry will have a new neap in the future.

2 Common Portland cement

Generally, the cement can be defined as a hydraulic powder material. When cement is mixed with proper amount of water, a plastic paste can be formed, which can harden both in the air and in water; and the sand, stone and other materials can be firmly combined together.

There are many types of cement, based on their application purpose and property. Three general types are common Portland cement, special cement and characteristic cement. Common Portland cement is widely used in civil engineer...

Table of contents

• Cover
• Title Page
• Copyright
• Preface
• Contents
• Brief introduction to the author
• 1 Introduction
• 2 Common Portland cement
• 3 Characteristic cement and special cement
• 4 Gypsum
• 5 Lime
• 6 Magnesia cementitious materials
• 7 Other binders
• Appendix
• Bibliography
• Index